Problems from The 2020 ICPC Vietnam National Contest

Languages
Astrological Sign0.003602478100841%2.2Easyen
Battle of Hogwarts0.0673384620524%6.0Harden
Cable Car0.002822274721%8.0Harden
Dividing Kingdom0.3417293297122%6.0Harden
Easy Arithmetic0.0816561985528%6.8Harden
Fluffy Cat0.0114321281915%7.9Harden
Greatest Pair0.6614345659316%6.6Harden
Highway to Mount Fansipan0.0334787424828%4.0Mediumen
Infinite 2D Array0.0445649015832%5.2Mediumen
Just Enough Water0.0070832712137%4.6Mediumen
Kingdom of Cats0.0074362518730%4.8Mediumen
Looping Around0.4718582514116%8.3Harden
Malfunctioning Robot0.0074115733229%3.6Mediumen